EFX crossover repair

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Mar 24, 2023
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Hello All,

I have an EFX and the inductor coils broke off. I was curious if anyone knew the specs on them? Or where martin logan buys them? I know they are 1.4mH and 4mH but after some research there are other specs involved that's above my comprehension. Any help would be appreciated
You can't salvage the inductors that broke off? Unwind a turn to get a useable wire to resolder?

As to matching new inductors, there's basically inductance and resistance, that needs to be matched. Matching inductance is fairly easy, since it's usually a known value. But, resistance can vary with the gauge of the wire, making finding a match more complicated. You'll probably have to measure for resistance, since it's not usually stated on a coil label. So, I'd match the gauge, inductance, and resistance as closely as possible, in order to match the stock speakers.

Check at U.S. Coils. They offer a nice range of inductors, in various gauges. They report the DCR reading too, to help with matching resistance.

Good luck.
The zip tie broke off and its loose. Does it need to be tightly wound? If so, I need new coils
The coils don't need to be beautiful, but the winding shouldn't be loose. So, if needed, I'd contact Martin Logan support for either new inductors, or the crossover schematic for the EFX speakers. Match inductance and resistance as closely as possible. If you can't get the exact coils through ML, I'd buy new coils for both speakers, to ensure they match one another.
Unfortunately they dont sell parts separately. You have to buy the entire crossover.
They should be able to give you the wiring diagram for the crossover. maybe you can match the parts if your comfortable with putting new ones in opposed to replacing the entire crossover?